Negation

The English words "must" and "should" express obligation distortedly.

Negation is essential to language, as it is essential to thought. Any concept (e.g. "red") exists because this concept can be applied or related to objects (including other concepts). Language allows representing knowledge, e.g. relationships and descriptions, in all matter of statements (e.g. "the ball is red"). When a relation between objects is stated, one is claiming presence: the presence of that relationship between the objects.

Also essential to thought is absence - the absence of a specific relationship between objects. Language expresses absence via negation, and (in English) uses words like "no", "not", and "none", to fit the various types of absences that we conceive.

In English, "must" and "should" are applied incorrectly to this pattern. "I must eat this cake" expresses that I have an obligation to eat this cake, and that not eating it would break some implied law, rule, or expectation, perhaps one set by a zealous host. This sentence states the presence of an obligation.

To state the absence of this obligation, the general pattern of negation brings one to say "I must not eat this cake". In common English, however, this construct does not comply. Such a sentence is understood to mean that I have an obligation to NOT eat this cake, that I am forbidden from it, and that eating it would break some implied law, rule, or expectation, perhaps one set by a rigorous mother. This sentence, the grammatical negation of the first, does not state an absence, but the presence of another obligation, one the opposite obligation of the first.

This grammatical inconsistency biases the English language towards obligation and restriction. Either this obligation holds, or its opposite does. One cannot express absence of obligation with these verbs. On one end I am tied to one restriction, and on the other I am tied to its opposite. "Must" and "should" inexorably hold restriction in their meaning, and are logically incomplete.

Life affects language and language affects life, and I think this grammatical quirk is both an effect and a cause of runoff polarization and radicalization of human ideologies. Similar impasses of obligation are often seen in our society. Either friend or foe. Either left-wing or right-wing politics. Either capitalism or communism. Either good or bad. When all must choose an extreme and no middle ground is allowed, antagonism becomes certain.

Some will argue that English is also able to express the absence of an obligation with other constructs. "I am allowed/free/able to not eat this cake" and "I don't need to eat this cake" express the absence of the first obligation, while "I am allowed/free/able to eat this cake" and "I am not forbidden to eat this cake" express the absence of the second obligation.

I argue that such constructs are not adequate complements to express the absence of obligation. Most of them are passive constructs, and as such hold lesser weight in their expression. And using the crutch-word of "need" as an equivalent word to "must" only overlaps the distinct meanings of necessity and of obligation, allowing semantic leakage (i.e. filling up a square hole with a triangular plug), and muddying up the meanings of both words and of our own minds. (Necessity indicates a lack/desire, while obligation indicates an expectation/restriction).

Whichever words we use, I believe it beneficial to clearly know what we mean.